S.T. Lee Lecture 2006
The exploration of Antarctic subglacial lakes: Science, logistics and politics
Professor Martin Siegert, 20 July 2006
Professor of Geosciences and Head,
School of GeoSciences, University of Edinburgh, United Kingdom
Synopsis of lecture
Over 145 lakes are known to exist beneath the Antarctic ice sheet. They range in size from a few hundred metres in diameter to the colossal Lake Vostok, which is over 240 km long. Since the discovery ten years ago that Lake Vostok had a water depth in excess of 500 m, biologists have considered subglacial lakes to be extreme environments where microorganisms, adapted to the distinctive conditions at the ice sheet base, may survive. In addition, geologists believe sediments at the floors of subglacial lakes may contain unique records of ice sheet and climate history. Hence, there are very good scientific reasons to undertake the exploration of subglacial lakes.
Plans to explore subglacial lakes have been in a phase of development for the past ten years, despite four major international conferences to advance the situation. The problem is twofold. First, undertaking direct measurement and sampling of a subglacial lake requires a huge logistical investment. Second, such exploration must guarantee against contamination of these pristine systems. Despite an international programme set up by the Scientific Committee on Antarctic Research to oversee the exploration of subglacial lakes, plans for the work remain varied and contentious.
The way forward requires consultation with, and agreement among, the members of the Antarctic Treaty. As a consequence, subglacial lake exploration has a political edge that is unusual in science. Nevertheless, several plans for subglacial lake exploration are being developed, including a Russian-led proposal to drill into Lake Vostok and a UK-led scheme to explore Lake Ellsworth in West Antarctica. These plans aim to unlock the scientific secrets of subglacial lakes within the next ten years.
Martin Siegert received his PhD in 1993 from the Scott Polar Research Institute, University of Cambridge, for numerical modelling studies of the Svalbard-Barents Sea Ice Sheet of the last Ice Age. Through his contact there with former Director, Gordon Robin, he became interested in subglacial Lake Vostok, Antarctica, which had then only just been discovered. His modelling work at the Centres of Glaciology at University of Aberystwyth (1994) and University of Bristol(1998) indicated that extensive areas beneath the Antarctic ice sheet were most likely melting, leading to the discovery from remote sensing records of over 170 subglacial lakes. As a consequence his research group has become interested in direct measurements and sampling of these lakes. Martin is co-principal investigator of ICECAP, a joint UK-US project using aircraft with remote sensing equipment to map the base of the Antarctic ice sheet in detail, the aim being to integrate these observations with more advanced modelling to improve our understanding of Antarctic ice sheet behaviour in the past and the future. He is also co-convener of the Antarctic Climate Evolution (ACE) Programme, one of five flagship science programmes of the Scientific Committee on Antarctic Research.